1. Field of the Invention
This invention relates to a compact planar antenna for wireless communication devices such as cellular telephones, PCMCIA cards, etc. More particularly, the compact planar antenna of this invention enables the antenna to be used in pairs or in linear array situations.
2. Description of the Related Art
A number of small patch or planar antennas have been previously provided which were generally useful for their limited intended purposes. In U.S. Pat. No. 6,157,344 (the ""344 patent), a patent owned by the assignee of the instant invention, a small indoor/outdoor, shock tolerant, flat panel, transmit/receive antenna is described. U.S. Pat. No. 6,249,254 (the ""254 patent), a patent owned by the assignee of the instant invention, describes the method of making the invention of the ""344 patent. The disclosure of the ""344 and ""254 patents are included herein by reference thereto. In the antenna of the ""344 patent, the radiating element thereof is triangular-shaped, or pseudo triangular-shaped, and which has two equal length sides that join to form an apex and having a base that is equal or unequal in length to the sides, thus placing the apex coincident with the antenna long axis. Although the antenna of the ""344 patent performs very well, it has been found that the antenna thereof is too large for some applications. The need thereof exists for a compact planar antenna which is smaller than the antenna of the ""344 patent but which has the proper gain, pattern, and bandwidth performance
A planar antenna is described which comprises a substrate fabricated from a commercial PCB laminate or other materials, and an antenna element formed on one side thereof which is formed in the shape of a right triangle or related shape. In some embodiments, a ground plane is provided on one or both sides of the substrate. In some embodiments, a pair of the antenna elements may be used. In other embodiments, a plurality of the antenna elements may be arranged in an array to increase the performance of the antenna.
It is therefore a principal object of the invention to provide a compact planar antenna which is small enough to be used in most applications.
Yet another object of the invention is to provide a compact planar antenna which is small enough to be used in most applications without sacrificing gain, pattern and bandwidth performance.
A further object of the invention is to provide a compact planar antenna which includes an antenna element in the form of a right triangle or related shape.
Yet another object of the invention is to provide a compact planar antenna which may be used in groups of two or more antennas in close proximity to one another.
Still another object of the invention is to provide a compact planar antenna including antenna elements which may be used in an array arrangement.
Yet another object of the invention is to provide a compact planar antenna which is less expensive to manufacture than certain other planar antennas.
These and other objects will be apparent to those skilled in the art.